Dr Sinead Murphy, a paediatrician in Temple Street Hospital, said more than half the children treated for serious weight problems were eating what we would consider "healthy food."

But there is "just far too much of it," she warned.

"We also know that the parents may feel they are doing the right thing for their children by filling them up with 'good food' when in fact they're creating problems for them now and in later life," she said.

"It's important to encourage children to recognise when they are full and to allow them not to eat any more when they feel full - most parents will go with this with sweet treats but not when it comes to other foods.

"This message from the campaign is critical and parents need to be aware that children only need child-sized portions of all foods and any more is doing them harm in the long-term."

Many parents are concerned they are not feeding their child enough and this causes them to overload plates.

As children return to school many parents worry even more.

However, Dr Cliodhna Foley-Nolan of Safefood advised using smaller child-sized plates at mealtimes.

"Give a smaller portion to begin with - if children are still hungry, then give a little bit more," she advised.

She pointed out there has also been a rise in the size of foods like scones, croissants, Danish pastries and takeaway foods in the last 20 years.

Some takeaway food portion sizes are now 180pc bigger that they were in the 1990s.

Tips include:

Try not to make your child finish everything on the plate or eat more than they want.

It may help if you encourage a child to eat slowly and have set mealtimes.

Beware of high-calorie foods. Knowing how many calories your child consumes each day, and balancing that with the amount of energy they use up in being active.

Children need about 60 minutes of physical activity a day.

When buying processed foods, check the nutrition label and choose those that are lower in sugar, saturated fat, and salt.